//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// <algorithm>

// template<InputIterator InIter, typename OutIter>
//   requires OutputIterator<OutIter, RvalueOf<InIter::reference>::type>
//   OutIter
//   move(InIter first, InIter last, OutIter result);

#include <cuda/std/__algorithm>
#include <cuda/std/cassert>
#if defined(_LIBCUDACXX_HAS_MEMORY)
#include <cuda/std/memory>
#endif // _LIBCUDACXX_HAS_MEMORY

#include "test_macros.h"
#include "test_iterators.h"

struct NonTrivialMove {
  int data = 0;
  bool move_assigned_from = false;

  NonTrivialMove() = default;
  __host__ __device__ TEST_CONSTEXPR_CXX20
  NonTrivialMove(const NonTrivialMove& other) noexcept
      : data(other.data),
        move_assigned_from(false) {}

  __host__ __device__ TEST_CONSTEXPR_CXX20
  NonTrivialMove(NonTrivialMove&& other) noexcept : data(other.data),
                                                    move_assigned_from(false) {}

  __host__ __device__ TEST_CONSTEXPR_CXX20 NonTrivialMove&
  operator=(const NonTrivialMove& other) noexcept {
    data = other.data;
    move_assigned_from = false;
    return *this;
  }

  __host__ __device__ TEST_CONSTEXPR_CXX20 NonTrivialMove&
  operator=(NonTrivialMove&& other) noexcept {
    data = other.data;
    move_assigned_from = true;
    return *this;
  }

  __host__ __device__ TEST_CONSTEXPR_CXX20
  NonTrivialMove(const int val) noexcept : data(val),
                                           move_assigned_from(false) {}
  __host__ __device__ TEST_CONSTEXPR_CXX20 NonTrivialMove&
  operator=(const int val) noexcept {
    data = val;
    move_assigned_from = false;
    return *this;
  }

  __host__ __device__ TEST_CONSTEXPR_CXX20 friend bool
  operator==(const NonTrivialMove& lhs, const NonTrivialMove& rhs) noexcept {
    // NOTE: This uses implicit knowledge that the right hand side has been moved from
    return lhs.data == rhs.data && !lhs.move_assigned_from &&
           rhs.move_assigned_from;
  }
  __host__ __device__ TEST_CONSTEXPR_CXX20 bool
  operator==(const int& other) const noexcept {
    // NOTE: This uses implicit knowledge that the only elements we compare against were untouched
    return data == other && !move_assigned_from;
  }
};

template <class InIter, class OutIter>
TEST_CONSTEXPR_CXX20 __host__ __device__ void test() {
  using value_type = typename cuda::std::iterator_traits<InIter>::value_type;
  {
    constexpr int N = 1000;
    value_type ia[N] = {0};
    for (int i = 0; i < N; ++i) {
      ia[i] = i;
    }
    value_type ib[N] = {0};

    OutIter r = cuda::std::move(InIter(ia), InIter(ia + N), OutIter(ib));
    assert(base(r) == ib + N);
    for (int i = 0; i < N; ++i) {
      assert(ia[i] == ib[i]);
    }
  }

  {
    constexpr int N = 5;
    value_type ia[N] = {1, 2, 3, 4, 5};
    value_type ic[N + 2] = {6, 6, 6, 6, 6, 6, 6};

    auto p = cuda::std::move(ia, ia + 5, ic);
    assert(p == (ic + N));
    for (int i = 0; i < N; ++i) {
      assert(ia[i] == ic[i]);
    }

    for (int i = N; i < N + 2; ++i) {
      assert(ic[i] == 6);
    }
  }
}

#if defined(_LIBCUDACXX_HAS_MEMORY)
template <class InIter, class OutIter>
TEST_CONSTEXPR_CXX20 __host__ __device__ void test() {
  constexpr unsigned N = 100;
  cuda::std::unique_ptr<int> ia[N];
  for (unsigned i = 0; i < N; ++i)
    ia[i].reset(new int(i));
  cuda::std::unique_ptr<int> ib[N];

  OutIter r = cuda::std::move(InIter(ia), InIter(ia + N), OutIter(ib));
  assert(base(r) == ib + N);
  for (unsigned i = 0; i < N; ++i)
    assert(*ib[i] == static_cast<int>(i));
}
#endif // _LIBCUDACXX_HAS_MEMORY

TEST_CONSTEXPR_CXX20 __host__ __device__ bool test() {
  test<cpp17_input_iterator<int*>, cpp17_output_iterator<int*> >();
  test<cpp17_input_iterator<int*>, cpp17_input_iterator<int*> >();
  test<cpp17_input_iterator<int*>, forward_iterator<int*> >();
  test<cpp17_input_iterator<int*>, bidirectional_iterator<int*> >();
  test<cpp17_input_iterator<int*>, random_access_iterator<int*> >();
  test<cpp17_input_iterator<int*>, int*>();

  test<forward_iterator<int*>, cpp17_output_iterator<int*> >();
  test<forward_iterator<int*>, cpp17_input_iterator<int*> >();
  test<forward_iterator<int*>, forward_iterator<int*> >();
  test<forward_iterator<int*>, bidirectional_iterator<int*> >();
  test<forward_iterator<int*>, random_access_iterator<int*> >();
  test<forward_iterator<int*>, int*>();

  test<bidirectional_iterator<int*>, cpp17_output_iterator<int*> >();
  test<bidirectional_iterator<int*>, cpp17_input_iterator<int*> >();
  test<bidirectional_iterator<int*>, forward_iterator<int*> >();
  test<bidirectional_iterator<int*>, bidirectional_iterator<int*> >();
  test<bidirectional_iterator<int*>, random_access_iterator<int*> >();
  test<bidirectional_iterator<int*>, int*>();

  test<random_access_iterator<int*>, cpp17_output_iterator<int*> >();
  test<random_access_iterator<int*>, cpp17_input_iterator<int*> >();
  test<random_access_iterator<int*>, forward_iterator<int*> >();
  test<random_access_iterator<int*>, bidirectional_iterator<int*> >();
  test<random_access_iterator<int*>, random_access_iterator<int*> >();
  test<random_access_iterator<int*>, int*>();

  test<int*, cpp17_output_iterator<int*> >();
  test<int*, cpp17_input_iterator<int*> >();
  test<int*, forward_iterator<int*> >();
  test<int*, bidirectional_iterator<int*> >();
  test<int*, random_access_iterator<int*> >();
  test<int*, int*>();

  test<NonTrivialMove*, NonTrivialMove*>();

#if defined(_LIBCUDACXX_HAS_MEMORY)
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_output_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_input_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        forward_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        bidirectional_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        random_access_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cpp17_input_iterator<cuda::std::unique_ptr<int>*>,
        cuda::std::unique_ptr<int>*>();

  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_output_iterator<cuda::std::unique_ptr<int>*> >();
  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_input_iterator<cuda::std::unique_ptr<int>*> >();
  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        forward_iterator<cuda::std::unique_ptr<int>*> >();
  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        bidirectional_iterator<cuda::std::unique_ptr<int>*> >();
  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        random_access_iterator<cuda::std::unique_ptr<int>*> >();
  test1<forward_iterator<cuda::std::unique_ptr<int>*>,
        cuda::std::unique_ptr<int>*>();

  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_output_iterator<cuda::std::unique_ptr<int>*> >();
  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_input_iterator<cuda::std::unique_ptr<int>*> >();
  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        forward_iterator<cuda::std::unique_ptr<int>*> >();
  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        bidirectional_iterator<cuda::std::unique_ptr<int>*> >();
  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        random_access_iterator<cuda::std::unique_ptr<int>*> >();
  test1<bidirectional_iterator<cuda::std::unique_ptr<int>*>,
        cuda::std::unique_ptr<int>*>();

  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_output_iterator<cuda::std::unique_ptr<int>*> >();
  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        cpp17_input_iterator<cuda::std::unique_ptr<int>*> >();
  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        forward_iterator<cuda::std::unique_ptr<int>*> >();
  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        bidirectional_iterator<cuda::std::unique_ptr<int>*> >();
  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        random_access_iterator<cuda::std::unique_ptr<int>*> >();
  test1<random_access_iterator<cuda::std::unique_ptr<int>*>,
        cuda::std::unique_ptr<int>*>();

  test1<cuda::std::unique_ptr<int>*,
        cpp17_output_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cuda::std::unique_ptr<int>*,
        cpp17_input_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cuda::std::unique_ptr<int>*,
        forward_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cuda::std::unique_ptr<int>*,
        bidirectional_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cuda::std::unique_ptr<int>*,
        random_access_iterator<cuda::std::unique_ptr<int>*> >();
  test1<cuda::std::unique_ptr<int>*, cuda::std::unique_ptr<int>*>();
#endif // _LIBCUDACXX_HAS_MEMORY

  return true;
}

int main(int, char**) {
  test();

#if TEST_STD_VER >= 2020
  static_assert(test());
#endif // TEST_STD_VER >= 2020

  return 0;
}
